In the car industry when a headlight burns out or does not function properly, the whole headlight assembly may need to be replaced. However, in some headlight assemblies only the light bulb is replaced. When the light bulb is replaced however, it is critical that the bulb is situated within the headlight assembly to very exacting standards so that the light coming out of the headlight is angled in the proper direction.
FIGS. 1 and 2 illustrate a known replacement lamp assembly. FIGS. 1a-1d illustrate a mounting strap 10 used in the mounting assembly. The mounting strap 10 has a stem 18 and a U-shaped channel formed at one end of stem 18. The U-shaped channel has three sides 16, 20 and 22, respectively. The first and second sides 20 and 22 are substantially parallel to each other and substantially perpendicular to the third side 16. The first and second sides 20 and 22 each have a flange 12 attached at an end opposite to the end connected to the side 16. The flange 12 is bent at an angle so that the angle formed between the outside of the second side 22 and the flange 12 is slightly less than perpendicular. As illustrated in FIG. 1b, the first and second sides 20 and 22 each have two projections 14 on their inner surfaces so that the projections extend into the U-shaped channel. The corners of the projection 14 are relatively sharp.
FIG. 2 illustrates a known replacement light bulb. The light bulb 30 has a bulb section 32 which contains a filament 34 and electrical contacts 37. The light bulb 30 also has a base section 36 through which the electrical connectors 37 exit the light bulb. The base section 36 has a flat pressed glass surface. Each of the main sides of the base section contains four depressions 38 for receiving the projections 14 on the mounting strap 10.
The replaceable light bulb 30 is secured between two mounting straps 10. First, the base section 36 of the light bulb 30 is positioned inside the U-shaped channel of the first mounting strap. The second mounting strap is then positioned opposite to the first mounting strap so that the base section 36 of the light bulb is inside the U-shaped channel of the second mounting strap. The base section 36 of the light bulb has a length that is sufficient to keep the two mounting straps from touching each other when they are positioned around the base section 36. The flanges 12 of the opposing mounting straps are then forced together and connected by rivets, or the like, to secure the pressed glass base of the light bulb between the mounting straps. When the flanges are forced together, the first and second sides 20 and 22 of the U-shaped channel are urged toward each other. Therefore, the mounting straps 10 must be aligned so that the projections 14 move into the depressions 38 when the two mounting straps are connected. Once the light bulb has been secured in the mounting straps 10, the stems of the mounting straps are inserted into a hot plastic holder which, when cooled, is used to secure the light bulb assembly in a head light.
One problem with the prior art assembly is the possibility of breaking the glass base of the light bulb during the mounting process. The sharp edges of projections 14 on the mounting strap slope away quickly from the top of the projections. As a result, if the projections 14 of the mounting straps are not perfectly aligned with depressions 38 in the glass base of the light bulb, the edges of the projections may break the glass base when the light bulb is mounted in the mounting straps. This problem is further exasperated by the fact that it is hard to properly align the depressions in the pressed glass base section with the projections on the mounting straps since there is no means for guiding the projections and depressions into proper alignment.
Furthermore, in the prior art assembly, the entire length of the first and second sides of the U-shaped body are contact surfaces for securing the light bulb. Therefore, the corners of the U-shaped body exert pressure on the corners of the pressed glass base 36. As a result, if the pressed glass base is not properly aligned, the corners of the pressed glass base may be pinched and possibly broken when the sides of the U-shaped body are moved together during the mounting operation.